The number of veterans receiving opioids from VHA providers increased from 651,000 in 2001 to 1,101,346 in 2013, with a substantial proportion receiving long-term opioid therapy (LTOT). Rising concerns regarding modest or absent benefit with LTOT as well as significant short- and long-term side effects have resulted in widespread efforts to curtail the use of opioids in the VHA. However, resources to support veterans who wish to taper are inadequate. Primary care, where most LTOT in VHA is prescribed, is overburdened and straining to meet the challenge of caring for patients with chronic pain. Pharmacist-run and other resource intensive clinical programs are effective, but may be too time or resource intensive to be feasible for many facilities. Furthermore, even well-resourced hub medical centers typically struggle to meet the needs of community- based outpatient clinics. A scalable, relatively inexpensive tapering intervention to support primary care and/or to extend the reach of resource-intensive specialty clinics would be of great benefit to veterans who are not deriving sufficient benefit from LTOT. As such, the goal of this proposal is to develop LIMIT (Less Is More In Opioid Treatment), an interactive, theory-informed, multi-component mobile website program to enable veterans to safely taper opioids. We will develop LIMIT using the Intervention Mapping (IM) framework, a rigorous protocol for developing effective behavior change interventions. To meet our objective, we propose the following specific aims: Aim 1. To develop LIMIT following the first four iterative steps of the IM protocol. We will develop a functional prototype based on the data generated from a needs assessment, change objectives, and proposed theory-based behavior change techniques. Key informants (including veterans and primary care providers) have and will continue to will be involved in the development of LIMIT to enhance usability, future dissemination and implementation. Aim 2. To pre-test the initial LIMIT prototype. We will perform iterative rounds of usability testing of the LIMIT prototype with four to six veterans on LTOT per round and then field test the refined mobile website program in a real-world setting. Usability will be tested using both qualitative and quantitative approaches and refinements will be made as required. Aim 3. To evaluate feasibility of a full-scale efficacy RCT of LIMIT. We will conduct a 9-month, randomized, two-arm, parallel, open-label, feasibility trial. Eligible participants will be randomized to LIMIT versus a pain monitoring app. Outcome measures will be collected over 9 months. To ensure rigor and successful future implementation, we will: 1) develop an evidence based program with features proven to maximize engagement and retention; 2) ensure that the program includes mechanisms to address the diverse obstacles veterans report when consider opioid tapering (e.g. fear of pain flares and abandonment by the system); 3) employ a User Centered Design ? with meaningful input from veterans and primary care providers throughout the development and testing phases; and 4) adhere to recently published guidelines for mobile health interventions.